All 1400 coronary bypass grafts, in 409 survivors of 414 patients undergoing 440 consecutive bypass operations, were selectively opacified in multiplane cineangiograms prior to hospital discharge and 1132 (81%) were restudied at one year. Grafts were graded A (excellent), B (fair) or O (occluded) by separate assessment of proximal and distal anastomoses and bypass trunks. In early graft studies 89% were patent (A and B), 79% graded A; at one year, 81% were patent, 74% graded A. Circumflex-marginal grafts fared less well early, but similarly late, compared with other grafts. Of all grafts graded B early, 37% became A, 39% remained B and 24% were occluded at one year; 90% of early graded A grafts remained so, 4% became B and 6% occluded; the grading system seems to have had useful predictive value. Distal anastomosis defects dictated early B grading in 81.3% of cases, trunk defects in 12.5% and proximal anastomosis defects in 2.7%. Trunk defects carried a worse prognosis for occlusion than did distal anastomosis defects. Side-to-side, vein-coronary anastomoses had a significantly higher patency rate than terminal end-to-side coronary anastomoses with the same veins.
FitzGibbon et al. (Thu,) studied this question.